I’ve seen this error twice, yesterday and today, when I started filling in a form on Mantis (either a new issue or a response), and waited too long to submit. It happened again just now, after maybe 30 min. Reloading the page allows me to re-enter/copy the content and proceed, but this limitation seems quite unfriendly to bug reporters, who are (ideally!) collecting and confirming information over a period of time while filling in, before actually submitting.
APPLICATION ERROR #2800 Invalid form security token.
I get this fairly often too, but fortunately if I just hit ‘back’ in the browser my note contents are still there and I can just click submit and everything is fine.
You are lucky. I get this error often, too, but for me the content is usually (maybe always) lost. If cannot be fixed then at least showing a warning could help (“submission has to be completed within X minutes, otherwise entered in text may be lost”).
I am getting the same error while trying to sign up to report a bug. It doesn’t seem to help to click “Back” and try again after trying it numerous times. Is there a way an account can be created for me?